Various compound and intermetallic semiconductors containing a pnictide are currently utilized in opto-electronic devices such as solid state lasers and light emitting diodes. In order to provide light guiding in and to and from these devices films are applied thereto having a lower index of refraction than the light containing semiconductor material. However, the native oxides of the semiconductor materials are not good film formers thereon and do not provide good adherence or good interface properties. In accordance with the above-identified U.S. patent application Ser. No. 581,115 filed herewith entitled PASSIVATION AND INSULATION OF III-V DEVICES WITH PNICTIDES, PARTICULARLY AMORPHOUS PNICTIDES HAVING A LAYER-LIKE STRUCTURE, pnictide rich thin films can be grown with good adherence and interface properties on semiconductors comprising a pnictide.